Contents

Project Management

Cause for Corrective Action

The decision to decentralize the work involved in completing Gate 3 by assigning each group member a specific task and having no group meetings proved to be highly effective in minimizing the total amount of time spent on the project while still providing an acceptable degree of quality. Given the fractured and busied nature of everyone in the group's schedule during this project gate, we will continue to use this method to complete Gate 4.

Product Explanation

Product Reassembly

Chris, Sam, and I will finish this out, but for now just flip all the entries in this table.

In the end we need to answer these:
How difficult is each step?
How can you define a meaningful scale to rate the difficulty?
How was the product originally assembled (by hand, robot, etc.)?
Is the assembly the same as the disassembly?

#

Step Description

Tool Used

Difficulty Rating

22

Pull sustain pedal bar out

None

1-1-1

The sustain pedal bar runs under the mutes. After the hinges are removed, the sustain pedal bar simply slides out from under the mutes.

Lifting up the very top panel of the piano exposes parts of the action and two hinges held on with screws that secure the top of the panel. Remove them to allow for easier access to the rest of the piano.

2

Remove bottom baseboard

None

1-1-1

There is a latch near the baseboard of the piano on the underside of the keys that holds the baseboard of the piano in. Flip it, and remove the baseboard.

3

Remove horizontal bar on top of sliding keyboard cover

Screwdriver

1-1-1

Now that the the top hatch and base board are removed, remove the horizontal bar that the top hatch rested on. The bar is held up with two screws on each side, so a screwdriver was used for the disassembly.

4

Remove keyboard cover

Screwdriver

2-1-1

The keyboard cover was attached to a hinge that allowed it to slide over the keys. Remove the screws holding it in to the side of the piano and lift out.

5

Remove Horizontal bar on top of keys

Screwdriver

1-1-1

This bar holds the keys in place, and must be taken off next. It was held in by evenly spaced screws along its length.

6

Remove steel pull-rods from key-levers

None

2-2-2

Upon initial inspection, it appears that the action can be removed at this step. This is not the case. The action is connected to the keys by a series of long metal rods capped with dowels that will prevent movement unless they are disconnected. To remove, slightly depress the key and pull the dowel off the key towards the action. Note the bright orange felt underneath the removed pull-rods at right.

7

Unscrew action bracket and lift out

Screwdriver

3-1-1

With the action disjoined from the keys, the only thing left holding it into the piano are screws on either side that attach to the piano body and screws to the back wall. These are unscrewed, and the action is carefully lifted out as to not disrupt the fragile members. Be sure to have at least one person holding up the unscrewed parts of the action.

8

Remove keys and key pin board

None

3-2-2

All of the keys are only attached by vertical pins on the pull rod board. The keys are easily removed using our hands, and their numbers are inscribed in their body, so order was easily maintained. We took the extra step of storing the keys taped together in numerical order to facilitate reattaching them.

9

Remove key pin board

None

2-1-1

The board the keys were attached to was secured to the frame of the piano with screws placed along its length. Unscrew them.

10

Detach pedal levers from pedals

Wrench, pliers

1-1-1

Release the pedal levers from pedals by unscrewing the threaded connector. These may be finger-tight or may require a wrench and pliers.

11

Remove pedal dowels

None

1-1-1

The pedal dowels connect the pedal lever to the action. A simple vertical pin protruding from the bottom of the dowel is the only mounting hardware. With the action removed, the pedal dowels simply lift out of the pedal levers.

12

Detach pedal levers from piano floor

Screwdriver

1-1-1

The pedal lever is attached to the piano floor by a flat spring. This spring is connected directly to the floor by two screws.

13

Remove pedal hinges and remove axle from pedal

Screwdriver

1-1-2

The pivot for the pedal is screwed into the floor. The axles are press-fit into these and the pedal. Once the pivot block is loose, the axle pulls out.

14

Unscrew pull-rod and associated lever

Screwdriver

1-1-3

With the action removed, the pull rod and the lever it activates can now be removed. It is joined to the action bracket with one screw and joined to the hammer by a cloth strap.

15

Unscrew hammer and remove

Screwdriver

1-1-3

The hammer pivot is screwed to the action bracket with one screw. It is also joined to the pull-rod lever by a cloth strap. Once both the pull-rod lever and the hammer are loose, they can be removed from the action bracket.

16

Unscrew mute

Screwdriver

1-1-2

The mute pivot is screwed to the action bracket by a single screw. After the screw is removed, take the mute off the action bracket.

17

Unscrew the iron bracket on the end of the action

Screwdriver

2-2-2

The action’s structure is held together and attached to the piano body with cast iron brackets at its ends and center. This is also held on by screws that are removed with screwdrivers.

18

Remove the una corda pedal bar

None

2-1-2

The una corda bar which runs behind the hammers pivots on the cast iron brackets in step 16. It is visible just above the bracket screws in the image at left. Once the brackets are loose, the una corda bar is free to drop from the action.

19

Remove spring bar

Screwdriver

2-1-3

A bar with thin springs to return the hammers to rest position runs between the mutes and hammers. Remove the four screws that secure it and slide it out of the action.

20

Unscrew the mutes above the hinges of the sustain pedal bar

Screwdriver

1-3-3

The metal sustain pedal bar runs behind all the mutes. Its hinges are also behind the mutes. To access the hinges of the sustain pedal bar, four mutes that cover the hinges' screws must be removed. Unscrew as in step 15.

21

Unscrew the hinges of the sustain pedal bar

Screwdriver

1-1-1

These hinges are held by screws to the action bracket. Remove the screws and slide the hinges off the axles on the sustain pedal bar.

22

Pull sustain pedal bar out

None

1-1-1

The sustain pedal bar runs under the mutes. After the hinges are removed, the sustain pedal bar simply slides out from under the mutes.

Mechanisms

"Your group must identify one or more mechanisms that your device uses to generate specific
motion, control system behavior, modify/condition energy, etc"

They say we only need one. I don't believe them.

First Mechanism

Technical Name

Purpose

"how the mechanism works"

Equations governing the design of the mechanism

Design Revisions

Based on our analysis of the piano so far, and our understanding of the GSEE factors, three different revisions to the traditional piano could be made that would modify its design on the system level. These revisions would address issues that we identified.

First Revision

One of the issues with the piano is that it is too large and heavy. This limits its mobility, as well as places where it can be used. A solution to this would to reduce the number of keys in the piano itself. By cutting the number of keys in half, this would greatly reduce the size of the piano and its overall weight. This would increase its overall mobility, and its smaller footprint would allow the piano to be placed in more locations. Taking note of societal factors, the keys that would be eliminated would be those at the two extremes of the note range. This would make sure that the piano could still play a large number of piano compositions, that hover around the notes near middle C.

Second Revision

A second solution could also address the issue of the size, weight, and mobility of a traditional piano. Most of the current piano's size and weight come from the soundboard. With enough experimentation and research, the soundboard could be modified so that the same sounds could be produced, while changing the strings length, orientation, and tension. By doing this, the overall structure of the piano could be much smaller and significantly lighter. This could be beneficial to the consumer from an economic standpoint, since less material would be needed to make it so the price would go down. This also would take note of global factors, as the piano could now be moved around much easier and be played in places that it could not be done before.

Third Revision

Another issue with the full size piano, is that it is difficult for children and people with small hands to extend their fingers far enough to consistently play certain chords. The solution for this would be to integrate auxiliary keys to the original piano set up, that would hit the notes of the chord with a single depressed key. This takes into account societal factors by increasing the number of people that can learn to play the piano, even before their have grown to the ideal playing size, or if they never will.